Require 'metadata' param in addmetadata item PUT docs

Author: mgrauer

core/controllers/components/ApiitemComponent.php

@@ -179,7 +179,7 @@ public function itemSetmultiplemetadata($args)
      * @path /item/addmetadata/{id}
      * @http PUT
      * @param id The id of the item
-     * @param metadata The metadata list to add or update, should be passed in the request body
+     * @param metadata The metadata list to add or update, must be passed in the request body
      * as 'application/json'.
      * @param revision (Optional) Item Revision number to set metadata on, defaults to latest revision.
      * @return item on success,

modules/api/controllers/components/ApiComponent.php

@@ -776,7 +776,7 @@ public function itemSetmultiplemetadata($args)
      *
      * @param token Authentication token
      * @param itemid The id of the item
-     * @param metadata The metadata list to add or update, should be passed in the request body
+     * @param metadata The metadata list to add or update, must be passed in the request body
      * as 'application/json'.
      * @param revision (Optional) Item Revision number to set metadata on, defaults to latest revision.
      * @return item on success,